<template>
  <div id="aCoursesList" class="bg-fa of">
    <!-- /课程列表 开始 -->
    <section class="container">
      <header class="comm-title">
        <h2 class="fl tac">
          <span class="c-333">全部课程</span>
        </h2>
      </header>
      <section class="c-sort-box">
        <section class="c-s-dl">
          <dl>
            <dt>
              <span class="c-999 fsize14">课程类别</span>
            </dt>
            <dd class="c-s-dl-li">
              <ul class="clearfix">
                <li>
                  <a title="全部" href="#">全部</a>
                </li>
                 <!-- v-for遍历  
                (item,index) index表示索引值，  比如item从1开始  index从0开始  :class类样式，和最下面的 .active对应active:oneIndex==index 这个值相等， acticve可以生效，有背景色选中，不相等，不相等，不选中
                item遍历得值，可以查id-->
                <li v-for="(item,index) in subjectNestedList" :key="index" :class="{active:oneIndex==index}">
                  <a :title="item.title" href="#" @click="searchOne(item.id,index)">{{item.title}}</a>
                </li>
               
              </ul>
            </dd>
          </dl>
          <dl>
            <dt>
              <span class="c-999 fsize14"></span>
            </dt>
            <dd class="c-s-dl-li">
              <ul class="clearfix">
                <li v-for="(item,index) in subSubjectList" :key="index" :class="{active:twoIndex==index}">
                  <a :title="item.title" href="#" @click="searchTwo(item.id,index)">{{item.title}}</a>
                </li>
               
              </ul>
            </dd>
          </dl>
          <div class="clear"></div>
        </section>
        <div class="js-wrap">
          <section class="fr">
            <span class="c-ccc">
              <i class="c-master f-fM">1</i>/
              <i class="c-666 f-fM">1</i>
            </span>
          </section>
          <section class="fl">
            <ol class="js-tap clearfix">
             <li :class="{'current bg-orange':buyCountSort!=''}">
                <a title="销量" href="javascript:void(0);" @click="searchBuyCount()">销量
                <span :class="{hide:buyCountSort==''}">↓</span>
                </a>
              </li>
              <li :class="{'current bg-orange':gmtCreateSort!=''}">
                <a title="最新" href="javascript:void(0);" @click="searchGmtCreate()">最新
                <span :class="{hide:gmtCreateSort==''}">↓</span>
                </a>
              </li>
              <li :class="{'current bg-orange':priceSort!=''}">
                <a title="价格" href="javascript:void(0);" @click="searchPrice()">价格&nbsp;
                  <span :class="{hide:priceSort==''}">↓</span>
                </a>
              </li>
            </ol>
          </section>
        </div>
        <div class="mt40">
          <!-- /无数据提示 开始-->
          <section class="no-data-wrap" v-if="data.total==0">
            <em class="icon30 no-data-ico">&nbsp;</em>
            <span class="c-666 fsize14 ml10 vam">没有相关数据，小编正在努力整理中...</span>
          </section>
          <!-- /无数据提示 结束-->
          <article  v-if="data.total>0" class="comm-course-list">
            <ul class="of" id="bna">
              <li v-for="item in data.items" :key="item.id">
                <div class="cc-l-wrap">
                  <section class="course-img">
                    <img :src="item.cover" class="img-responsive" :alt="item.title">
                    <div class="cc-mask">
                      <a :href="'/course/'+item.id" title="开始学习" class="comm-btn c-btn-1">开始学习</a>
                    </div>
                  </section>
                  <h3 class="hLh30 txtOf mt10">
                    <a :href="'/course/'+item.id" :title="item.title" class="course-title fsize18 c-333">{{item.title}}</a>
                  </h3>
                  <section class="mt10 hLh20 of">
                    <span v-if="Number(item.price) === 0" class="fr jgTag bg-green">
                      <i class="c-fff fsize12 f-fA">免费</i>
                    </span>
                    <span class="fl jgAttr c-ccc f-fA">
                      <i class="c-999 f-fA">9634人学习</i>
                      |
                      <i class="c-999 f-fA">9634评论</i>
                    </span>
                  </section>
                </div>
              </li>
              
            </ul>
            <div class="clear"></div>
          </article>
        </div>
        <!-- 公共分页 开始 -->
        <div>
      <div class="paging">
        <!-- undisable这个class是否存在，取决于数据属性hasPrevious -->
        <a
          :class="{undisable: !data.hasPrevious}"
          href="#"
          title="首页"
          @click.prevent="gotoPage(1)">首</a>
        <a
          :class="{undisable: !data.hasPrevious}"
          href="#"
          title="前一页"
          @click.prevent="gotoPage(data.current-1)">&lt;</a>
        <a
          v-for="page in data.pages"
          :key="page"
          :class="{current: data.current == page, undisable: data.current == page}"
          :title="'第'+page+'页'"
          href="#"
          @click.prevent="gotoPage(page)">{{ page }}</a>
        <a
          :class="{undisable: !data.hasNext}"
          href="#"
          title="后一页"
          @click.prevent="gotoPage(data.current+1)">&gt;</a>
        <a
          :class="{undisable: !data.hasNext}"
          href="#"
          title="末页"
          @click.prevent="gotoPage(data.pages)">末</a>
        <div class="clear"/>
      </div>
    </div>
      </section>
    </section>
    <!-- /课程列表 结束 -->
  </div>
</template>
<script>
import courseApi from '@/api/course'

export default {
  data() {
    return {
      page:1, //当前页
      data:{},  //课程列表
      subjectNestedList: [], // 一级分类列表
      subSubjectList: [], // 二级分类列表

      searchObj: {}, // 查询表单对象（传到接口中，做查询）

      oneIndex:-1,//一级分类，选择
      twoIndex:-1,//二级分类选择
      buyCountSort:"",//关注度
      gmtCreateSort:"",//最新
      priceSort:""//价格
    }
  },
  created() {//在页面渲染前，执行
    //课程第一次查询
    this.initCourseFirst()
    //一级分类显示
    this.initSubject()
  },
  methods:{
    //1 查询第一页数据
    initCourseFirst() {//通过response得到值，赋值给data变量/两个data得到，接口map集合
      courseApi.getCourseList(1,8,this.searchObj).then(response => {
        this.data = response.data.data
      })
    },

    //2 查询所有一级分类
    initSubject() {
      courseApi.getAllSubject()
        .then(response => {//既有一级分类，又有，二级分类
          this.subjectNestedList = response.data.data.list
        })
    },

    //3 分页切换的方法 /page页码数，查第几页的数
    gotoPage(page) {
      courseApi.getCourseList(page,8,this.searchObj).then(response => {
        this.data = response.data.data
      })
    },
       //4.点击某个一级分类，查询对应二级分类 searchOne上面点击事件得方法
       //subjectParentId自己起的名字  //searchObj查询条件值
       searchOne(subjectParentId,index){
         //把传递index值赋值给oneIndex，为了active样式生效
         this.oneIndex = index
         
         //把二级分类id清空
         this.twoIndex = -1
         this.searchObj.subjectId = ""
         this.subSubjectList =  [] //给集合赋值
         //this.searchObj.subjectParentId = subjectParentId
         // 3.里面得searchObj  . 后面是后端CourseFrontVo 里面的id =  searchOne(subjectParentId,index)里的subjectParentId
         //把一级分类点击id值，赋值给searchObj ，searchObj，把值用json传到接口中
         this.searchObj.subjectParentId = subjectParentId
         //点击某个一级分类进行条件查询  查询显示第一页（1）
          this.gotoPage(1)
         //拿着点击一级分类 id和所有一级分类id 进行比较，
         //如果id相同，从一级分类里面，获取对应得二级分类
         //下面遍历
         for(let i=0;i<this.subjectNestedList.length;i++) {
        //获取每个一级分类
        var oneSubject = this.subjectNestedList[i]
        //比较id是否相同
        if(subjectParentId == oneSubject.id) {
          //从一级分类里面获取对应的二级分类
          this.subSubjectList = oneSubject.children
        }
      }

       },
       //5.点击某个二级分类实现查询(二级分类id 和index)
       searchTwo(subjectId,index) {
       //把index赋值,为了样式生效
       this.twoIndex = index
        //把二级分类点击id值，赋值给searchObj ，searchObj，把值用json传到接口中
         this.searchObj.subjectId = subjectId
         //点击某个二级分类进行条件查询  查询显示第一页（1）
          this.gotoPage(1)
    },
    //6.根据销量排序
    searchBuyCount(){
     //设置对应变量,为了样式生效  searchObj要把对象传到接口中
     this.buyCountSort = "1"
     this.gmtCreateSort = ""
     this.priceSort =""

     //把值赋值到searchObj
      this.searchObj.buyCountSort = this.buyCountSort
      this.searchObj.gmtCreateSort = this.gmtCreateSort;
      this.searchObj.priceSort = this.priceSort;

      //调用方法查询 默认第一页
      this.gotoPage(1)
    },
    //7.最新排序
    searchGmtCreate() {
    //设置对应变量,为了样式生效  searchObj要把对象传到接口中
     this.buyCountSort = ""
     this.gmtCreateSort = "1"
     this.priceSort =""

     //把值赋值到searchObj
      this.searchObj.buyCountSort = this.buyCountSort
      this.searchObj.gmtCreateSort = this.gmtCreateSort;
      this.searchObj.priceSort = this.priceSort;

      //调用方法查询 默认第一页
      this.gotoPage(1)
    },
    //8.价格排序
    searchPrice() {

     //设置对应变量,为了样式生效  searchObj要把对象传到接口中
     this.buyCountSort = ""
     this.gmtCreateSort = ""
     this.priceSort ="1"

     //把值赋值到searchObj
      this.searchObj.buyCountSort = this.buyCountSort
      this.searchObj.gmtCreateSort = this.gmtCreateSort;
      this.searchObj.priceSort = this.priceSort;

      //调用方法查询 默认第一页
      this.gotoPage(1)
    }
  }

};
</script>
<style scoped>
  .active {
    /* 背景色 */
    background: #bdbdbd;
  }
  .hide {
    /* 不显示 */
    display: none;
  }
  .show {
    /* 显示 */
    display: block;
  }
</style>